Communication systems employing multiple channels, i.e. lanes, may carrying data with forwarded or embedded clock information. These communication systems should have some means of deskewing the received information before further data processing can be done. Skew can be a term referring to when two or more signals originally start out with a known timing relationship but lose the time reference with respect to each other. The signals should be deskewed to restore the timing relationship.
A previous deskewing approach typically uses a deskewing state machine in the data link layer to compensate for skew between the lanes. The compensating time period is a set period of time normally a set number of bits established by the platform guidelines. This lane-to-lane skew cancellation by the data link-layer may introduce a high latency penalty since the data link-layer for a typical serial I/O interface runs at a slower clock frequency than the clock frequency found in a typical I/O interface circuits.
Some deskew techniques may use an extra step of externally analyzing an amount of skew by a component external to the I/O circuit to then implement a mechanism to correct the amount of skew present in each lane with respect to the other lanes.
While the invention is subject to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and will herein be described in detail. The embodiments of the invention should be understood to not be limited to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.